Gas operated gun



Jan. 4,l 1966 T. w. sPAcK 3,227,148

GAS OPERATED GUN Filed Jan. 1l, 1961 2 Sheets-Sheet 1 T. W. SPACK GASOPERATED GUN Jan. 4, 1966 2 Sheets-Sheet 2 Filed Jan. ll. 1961 UnitedStates Patent O 3,227,148 GAS OPERATED GUN Theodore W. Spack, WebsterGroves, Mo., assignor to Benjamin Air Rifle Company, St. Louis, Mo., acorporation of Missouri Filed Jan. 11, 1961, Ser. No. 82,077 12 Claims.(Cl. 124-11) This invention relates to gas' operated guns in which acompressed gas is applied as the propellant. However, the improvementshereinafter disclosed may in certain respects be applied to other typesof guns.

An object of the invention is to provide a gun with a simple andeffective safety which prevents the hammer from becoming cocked whilethe breech is open, thereby assuring complete safety during loading andinspection `of the breech and magazine.

It is also an object of the invention to provide a gas operated gun withmeans for controlling vand variably setting the power chargeavailablefor expelling the pellets, and for releasing the gas pressurewhen desired.

A further object of the invention is to provide auto-l matic pellet feedmeans and means to control the pellets `in such manner that one pelletat a time is positioned for `valve means and the hammer., The foregoingassembly is suitably mounted upon a hand grip or stock, as the ease maybe, in which the trigger mechanism is housed. These and other featuresof the invention will become `more fully understandable during thecourse of present- ;ing the following description of the preferredconstruction,

reference being made tothe accompanying drawings, in which:

FIG. 1 is a side elevational View of a pistol havingy portions .thereofbroken away and shown in section; FIG. 2 is a top plan view of thepistol of FIG. 1; FIG. 3 is a greatly enlarged view of a safety deviceincorporated in the gun of FIG. l, the view being taken `at line 3-3 insaid FIG. l;

FIG, 4 is a greatly enlarged and fragmentary `side elevational viewshowing more of the details of the gun; and

FIG. 5 is a transverse sectional view taken at line 5-5 inFIG. 4.

Referring to FIGS. 1 and 2, the gun 10 has a tubular barrel 11 suitablysecured to a hand grip or stock 12 in which the trigger 13 and relatedmechanism to be described later is operably mounted. The barrel carriesa tubular cover 14 in which are housed a shot tube 15 and a magazinetube 16 in communication at the breech 17 of the shot tube 15. A shotfollower guide tube' 18 (FIGS. 2 and 5) is positioned adjacent one sideof the cover 14 and barrel 11 and is suitably secured to either or bothparts. The barrel 11, shot tube cover 14 and guide tube 18 are closelynested in tangential relation (FIGS. 2 and 5) and have theirlongitudinal axes in parallel relation to form a compact assembly havinga` lformed with a threaded forward open end 20 to receive a plug device21 to be described in more detail. The

chamber 22 at the forward end portion of the barrel is adapted toreceive a conventional CO2 cylinder 23, and a bulkhead disc 24 issecured at the inner end of such chamber by a suitable resilientretainer ring element 25. Spaced from the bulkhead 24 is a valve block26 which is secured in the barrel by a ferrule 27 which extends into thecover 14. The block is formed with an axial passage 28 open at a forwardlip 29 and with a radial passage open to the ferrule 27. The spacebetween the valve block 26 and the bulkhead 24 contains a suitable valveelement 30 having a seat gasket 31 which seats on the lip 29 and acombined guide and metering pin 32 which slides in the bulkhead 24 andhas a loose lit so that gas may freely pass. A spring 33 is mounted onthe pin 32 and abuts the bulkhead at one end and the enlarged valveelement 30 at its opposite end. The spring 33 acts to hold the seatgasket 31 upon the lip 29 thereby cutting off gas flow to the ferruletube 27. The valve element 26 is further guided by a hammer strikepin 34having a bearing sleeve 35 thereover which slides in a bore in the valveblock 26. The strike pin 34 projects rearwardly into a` hammer chamber36in the barrel.

In FIG. l, the rear end of the barrel is closed by a block element 37held therein by a threaded element 38 which also secured the grip 12 tothe barrel 11. The block 37 carries a guide element 39 on which a hammerspring 40 is mounted. Telescoped over the guide element 39 is the hammer41, and the spring 40 works between the closure block 37 and the innerend of the spring containing bore 42 in the hammer 41. The hammer 41 isformed with an annular groove 43 near its inner end, which groove isadapted to catch on the detent end 44 of a relay lever 45 which ispivotally mounted on a pin 46 in the grip 12. The relay lever 45 isurged in a clockwise direction, as viewed in FIGS. 1 and 4, by a springarm 47, the opposite end 48 of said spring being fixed against a stop 49in the grip 12. The relay lever has an actuating arm 50 which is engagedby the arm 51 which is a part of the trigger 13. The trigger is movablymounted on a pin 52 in the grip 12 so that the arrn 51 is movableclockwise to actuate the release arm 51 and is forced m a counterclockwise direction by the relay spring arm 47 acting on the relay. Aconventional rotary type trigger safety lock is shown at 53 in thesafety position, and need not be described since its function isunderstood.

There is shown in FIG. 2 a hand operated cocking" slide 54 having thepull handle 55 thereon. The slide is connected to the hammer 41 by theconnecting means 56 which operates in a slot (not shown) formed in theside of the barrel 11. This slide 54 is shown inthe cocked position tocorrespond with the hammer position of FIG. 1, but when the gun isdischarged it moves forward under the action of the spring 40 when therelay detent 44 is released from the hammer groove 43 upon actuation ofthe trigger 13 as is well understood.

With reference to FIG. 4 in particular', the ferrule 27 has its bore incommunication with an annular cavity 58 around the breech end 17 of theshot tube 15 and inside the cover 14. The cavity 58 is formed by anannular land 59 at its forward end and by an enlarged end portion 60 atthe forward end of the magazine tube 16. 4The cavity is in communicationwith the breech of the' shot tube 1 5 through radial ports 61 so thatgas released at valve port 29 may enter behind the head end 62 of thepellet P first in line. Gas leakage along' the' outside of the shot tube15 and the magazine tube 16 is prevented by O-ring seals 63 and 64respectively. Thus the gas charge is conlined to the discharge of thepellet P from the breech 17.

It has been found that the discharge of the leading pellet P creates adraw or suction effect upon the following pellets in the magazine tube16 and this reduces the pellet discharge power as well as causesundesirable positioning of subsequent pellets. To overcome this faultthe forward end portion 60 of the magazine tube 16 is made slightlysmaller in diameter than the internal diameter of the cover 14 for itslength from the O-ring seal 64 to the breech 17. This zone of themagazine tube is further provided with one or more axially spacedradially directed series of apertures 65 (two series being shown) whichopen behind seats 66 of suitable form which retain small O-ring elements67. A portion of the innermost surfaces of the O-ring elements 67project into the bore of the magazine tube 16. The exposed surfaces formretainers for the following pellets P so that these pellets are held inproper position and do not become displaced during the firing of theleading pellet P. The O-ring seals 67 also act to prevent or reduce thereverse escape of the gas charge so that a full gas charge is available.The elfectiveness of the O-ring seals 67 is greatly increased byproviding a passage 68-along the outer side of the magazine tube endportion 60, which passage 68 communicates with the apertures 65 andsupplies gas under pressure to the O-ring seals 67 to compress the samemore tightly about the pellets P at the moment of firing. Once the gascharge is exhausted, the seals 67 relax and allow relatively freedisplacement of the pellets for the next shot.

In combination with the foregoing novel improvement,

.the mechanism includes a positive mechanical shot or pellet stop whichtakes the form of a stop finger 70, movable into the reduced waist zoneof the pellet next in line for entry into the breech. The finger 70(FIGS.

v1 and 4) is actuated by a slide 71 which is movable in a slide passage72 formed in the valve block 26 behind the ferrule position. The slidehas an enlarged slot 73 therein so that it may straddle the pin 34 andits bearing sleeve 35 and move freely through the passage 72. A suitablespring 74 urges the slide in a direction to hold the finger 70 fullywithdrawn from the magazine tube bore (FIG. 1). The opposite end 75 ofthe slide 71 .projects into abutment with the end portion 50 of therelay 45 adjacent the trigger arm 51 so as to be responsive to actuationof the trigger when firing the gun. It is understood that as the triggeris pulled, the slide 71 lis moved upwardly to raise the stop finger 70so that at the instant of hammer (dotted line position of detent 44)-release the finger 70 (dotted line position) has fixed the pellet Pnext in line to the one about to be discharged.

`This action may be accomplished only when the safety is rotated to theoff position (dotted outline in FIG. 4).

In FIGS. 1, 3 and 2 there has been shown a novel device for renderingthe gun safe from accidental discharge during loading pellets into themagazine 16. This device includes a plate 77 having a circular baseportion l78 which fits over the closure block 37 of the barrel 11 `andis pivotally secured thereto by threaded element 79 which is positionedin the axial center of the block 37.

.The base portion 78 supports a circularly shaped closure portion 80which is normally positioned to cover the inlet end 81 of the magazinetube 16, and a rear gun sight plate 82 is carried by the portion 80. Thesight plate y82 is suitably notched at 83 to cooperate with the frontsight 84 (FIG. 1). The safety plate device 77 is releasably held in itsnormal position of FIG. l by a detent element 85 slidably mounted in theblock 37 at a position eccentric to the center pivot element 79. Thedetent velement85 normally seats in a recess 86 in the inner face .ofthe plate portion 78 under the action of a spring 87 behind the detent,and the detent is guided by an extension pin 89 which projects throughthe block 37 and into the hammer-chamber 36. When the plate device 77 isin its normal position the detent 85 is forced into the recess 86 andthe pin 89 is sufiiciently withdrawn from the chamber 36 so as not tointerfere with the desired cocking stroke of the hammer 41. However,when the device is swung laterally about its pivot 79 the detent iscammed inwardly by the relief contour 90 on the recess 86 so that thepin 89 is pushed into the chamber 36 and prevents the hammer 41 frombeing drawn rearwardly sufficiently far to be cocked on the detent 44 ofthe trigger relay lever 45. The swinging of the device 77 opens themagazine tube 16 for reloading, but if the hammer is in its cockedposition the device cannot be moved since the detent is unable to movedue to interference between the pin 89 and the hammer 41. Therefore, thehammer must first be released from its cocking detent 44.

Once the device 77 is free to be swung aside, the magazine tube 16 isaccessible. It then is necessary to withdraw the follower plunger 90from the tube 16 to reload. The plunger 90 is connected by arm 91 to ahandle 92 (FIG. 2) which moves along the side of the cover 14, the arm91 being movable in a suitable slot (not shown) in the side of the coveradjacent the guide 18. The handle 92 is connected to a guide rod 93 inthe guide 18 and this rod is spring loaded by an elongated spiral spring94 (FIG. 5) to pull the rod 93 rightwardly as viewed in FIG. 2, thespring being housed in the guide 18. When the follower plunger 90 hascleared the outer end of the magazine tube 16 it may be rotated sidewiseto leave the tube 16 unobstructed for loading pellets P.

Turning now to FIG. 1 the plug device 21 threaded into the barrel 11 at20 comprises a body 95 suitably formed to provide an annular seat for anO-ring seal 96. The body has an axial bore 97 to receive a threaded stem98, the stem having an enlarged inner end 99 in the bore 97 with anO-ring seal therein. The outer end of the stem 98 carries a poweradjusting knob 100 which is locked to the stem by a set screw 101. Thestern is formed with a bore to slidably mount a pressure relief valve102 located in the enlarged bore 97 and adapted to engage the adjacentend of the CO2 cylinder 23. The valve 102 is actuated by a button 103housed in the outer end of the knob 100, said button moving the reduceddiameter end 98 against the valve 102. The relief valve 102 is a plug ofnylon or other suitable material which when forced against the end 98 ofthe stem seals the gas against leakage along the stem 104 connecting thevalve and button 103. Variations in adjustment are obtained by settingthe end 99 of the stem 98 more inwardly or outwardly from the positionshown in FIG. 1. This setting determines the position of the valve 102which normally is pushed by the gas pressure tightly against the end 99.The resulting setting of valve 102 determines the position of the CO2cylinder in chamber 22 and therefore locates the distance between themouth 105 of the CO2 cylinder and the piercing end 106 of the valvestern 32. A lesser charge of gas to the breech 17 is obtained byshortening the travel of the stem 32 to cause the end 106 to abut themouth 105 of the CO2 cylinder. The abutment does not displace thecylinder since it is held by the relief valve 102 so that the valve 30is only open for a short time. A greater charge of gas is obtained bysetting the end 99 farther back in the body 95 so that the relief valve102 is farther back and spaces the CO2 cylinder farther from the stern32 so that the valve 30 is open for a longer time interval. Should it benecessary to relieve the gas pressure from chamber 22, the button 103 ispushed in to move relief valve 102 away from its seat on the end 99 ofstem 98. This action allows the gas to bleed out along the stem 104 toatmosphere until it is safe to remove the device 21.

While the foregoing has described a preferred construction illustratedin the accompanying drawings, the arrangement of parts and componentsmay be varied or modified without departing from the principles of theinvention. No unnecessary limitation is to be inferred except such asmay be required by the claims appended hereto.

What is claimed is:

`1. .In a gun assembly, a hand grip, an elongated tubular i rel andcover, and shot follower means operably carried by said guide tube andhaving a member extending into said magazine tube from said one openend.

2. In a gun assembly, a hand grip, an elongated barrel secured to saidgrip and providing a plurality of spaces for operating mechanism, anelongated cover disposed alongside of and secured to said barrel inparallel relation and at the side of said barrel opposite said grip, ashot tube and a magazine tube carried in said cover in axial alignment,a shot follower member movably mounted in said magazine tube, anelongated guide tube disposed in parallel relation along side saidbarrel and cover with one end adjacent the location of said magazinetube, and follower means guided by and movable in said guide tube andhaving a connection withsaid shot follower.

3. In a gas operated gun, a barrel member having a gas supply chamberadjacent one end and a hammer chamber adjacent the opposite end, a valveblock member separating said chambers and having a seat and a gas ilowpassage extending from the seat through a side of said barrel to a gasoutlet, a valve element normally closing said seat to shut off the ilowof gas, a spring loaded valve actuating hammer member in said hammerchamber, trigger mechanism on the gun including a lever releasablyengaging said hammer member in cocked position, a shot tube on saidbarrel having a breach end adjacent said gas outlet, a magazine forpropellable shot communicating with said breach end to feed shot intosaid breach end one at a time, and shot stop means in said gun includinga resilient element carried by said magazine adjacent said breach end toengage a propellable shot in advance of movement into said shot tubebreach end an element operably carried by said barrel member and havinga finger thereon extended into said magazine in response to said triggermechanism to release said hammer member to intercept the shot nextfollowing that one in said breach end of the shot tube.

4. The gas operated gun set forth in claim 3, wherein said shot tube andmagazine are arranged in axial alignment, and including a cover for saidshot tube and magazine, and seal means is engaged between said cover andeach of said shot tube and magazine on either side of said breach toprevent escape of gas through said cover.

5. The gas operated gun set forth in claim 3, wherein said magazineadjacent to said breach end of said shot tube is formed with an internalseat and said resilient element is disposed in said seat in position toengage a propellable shot and impede its movement during discharge of ashot in said breach end, and said magazine is formed with a passageopening at said internal seat to deliver gas to said seat to urge saidelement more tightly into engagement with a propellable shot.

6. The gas operated gun set forth in claim 5, including a coverenclosing said shot tube and magazine, seals between said cover and shottube and magazine, said seals being spaced apart on either side of saidbreach end to prevent escape of gas from said breach end, said resilientelement being responsive to the ow of gas directed by said cover to saidmagazine passage to expel a shot from said breach end to close upon a`shot in said magazine adjacent thereto and hold the same againstdisplacement.

'7. In a gas operated gun, a barrel, a valve block secured in saidbarrel and having a gas flow passage therein formed with an inlet seat,a valve for controlling said inlet including an actuating sternextending past said d valve block into the barrel, a spring loadedhammer member movably carried in said barrel and operable between acocked position and a position to strike said actuating stem and unseatsaid valve, means closing said barrel and forming an abutment for saidhammer in its cocked position, trigger mechnism in the gun operable toretain said hammer member in its cocked position, and safety means onthe gun to prevent cooking of said hammer member comprising a pinmovably mounted in said barrel closing and hammer abutment means andhaving one end movable into said barrel to hold said hammer member outof its cocked position, the opposite end of said pin movable out of saidclosing means, and a member movable on ='said barrel closing and hammerabutment means and having a recess therein which is positionable toreceive the opposite end of said pin and permit cooking of said hammermember, movement of said last member out of its iirst said positionplacing the gun on safety.

8. In a gas operated gun, a grip, trigger mechanism 0perable in saidgrip, a barrel on said grip having a hammer space adjacent said grip, agas control valve assembly in said barrel defining one end of the hammerspace, a valve in said assembly having a stem projecting into saidspace, a member in the end of said barrel closing said space, hammermeans reciprocably mounted in said space to move from a cocked positionadjacent said closing member to strike said valve stem, said hammerbeing retained in its cocked position by said trigger mechanism, andmeans to prevent said hammer reaching its cocked position including anabutment pin element movable through said closing means between aposition with one end extending into said space to stop movement of saidhammer means into cocked position and a position with the opposite endprojecting outwardly of said closing means and said one end retractedfrom said space, and abutment pin element control means at the exteriorof said barrel in operable connection with said element, said controlmeans comprising a member pivoted on said closing means and manuallymovable between said positions, said member having a recess cam thereinreceiving the opposite end of said abutment pin element in the secondnamed position of said abutment pin element.

9. A gas operated gun comprising, a barrel, a cover and a guide arrangedin a cluster, said barrel and cover having gas ow communication, asource of gas under pressure in said barrel, valve means in said barrelcontrolling gas flow to said cover, a shot tube and a magazine in saidcover arranged in communication with each other at a breach adjacent thegas flow communiaction to said cover, seal means in said cover on eitherside of said breach to confine the gas therein, propellable shot in saidmagazine, other seal means in said magazine engaging at least one ofsaid shot to form therewith a plug to resist gas flow reversely intosaid magazine, a shot follower in said magazine behind the shot andspring loaded means in said guide connected to said shot follower tocooperate in urging said shot toward the breach, a valve control hammerin said barrel movable from a cocked position to open said valve, andsafety means including a closure for the magazine having a normal closedposition and movable to one side to open the same for loading shot andan element movable in response to said closure movement to one side toblock said hammer from reaching its cocked position while the magazineis open.

10. The gun set forth in claim 9, wherein said other seal means is incommunication with the gas flow into said cover and contracts about theshot with each valve opening reaction to said hammer.

11. The gun set forth in claim 9, wherein said shot follower isremovable from said magazine and is supported by said spring loadedmeans, and said safety means in its normal position preventing said shotfollower from being removed.

12. The gun set forth in claim 9, wherein said closure of the safetymeans is formed with a sighting opening,

and said cover carries a cooperating sight remote from said magazine.

References Cited by the Examiner UNITED STATES PATENTS Burgher.

Falk.

Lefever 124-30 Straub 124-11 Johnson 124-52 X Foster 124-52 X Gale124-11 Martin 124-11 Hamrick 124-30 Cardin et al. 124-11 RICHARD C.PINKHAM, Primary Examiner.

JAMES W. LOVE, Examiner.

1. IN A GUN ASSEMBLY, A HAND GRIP, AN ELONGATED TUBULAR BARREL MOUNTEDON SAID GRIP AND PROVIDING AXIALLY ALIGNED CHAMBERS FOR OPERATINGMECHANISM, AN ELONGATED TUBULAR COVER MOUNTED IN PARALLEL RELATION ANDFIXED ON SAID BARREL OPPOSITE TO SAID GRIP, A SHOT MAGAZINE TUBE IN SAIDCOVER AND OPENING FROM ONE END THEREOF, AN ELONGATED GUIDE TUBE MOUNTEDIN PARALLEL RELATION TO SAID BARREL, MAGAZINE